In switching between Sram 1x, etap, and a Shimano Di2 TT, 2x mech - it takes a few shifts to have that memory recall. Then only afterwards it’s only during big effort moments when your concentration lapses for a split second do I ever misfire. So I’ll say 99% not an issue but when it happens I definitely pay for it, like accidentally switching to the big gear going up a steep hill.